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At least 1,423 records · Page 79Linked to original sources
PubMed2006

Stapedectomy in congenital stapes fixation: are hearing outcomes poorer?

OBJECTIVE: To evaluate outcomes of stapedectomy surgery for congenital stapes fixation. STUDY DESIGN: Retrospective chart review. METHODS: The charts of 463 stapedectomies performed by 1 surgeon from 1996 to 2003 were reviewed. Patients with a history of childhood hearing loss and operative findings consistent with congenital fixation of the stapes were included. Patients with a history of trauma or chronic otitis media and those with otosclerosis were excluded. Thirty-six patients underwent stapedectomy for congenital fixation. Revision cases and those with inadequate postoperative bone or air conduction data were excluded. Inclusion criteria were met for 25 patients. Operative findings and hearing outcomes were evaluated. RESULTS: The study group was comprised of 25 stapedectomies. Closure of the air-bone gap to less than 10 dB was achieved in 48% of cases, and 80% had closure within 20 dB. A gap of more than 30 dB remained in 3 cases. There were 2 cases of sensorineural hearing loss with worsening of the bone conduction thresholds by 15 dB and 30 dB. There were no instances of perilymph gusher. In addition to an excluded case that was not reconstructed because of facial nerve position, 3 of the included patients were found to have a dehiscent facial nerve at surgery. There were no facial nerve injuries, and fixation of the malleus or incus was not found in any of the included patients. When hearing outcomes were compared with our results for otosclerosis over the same time period, rates of closure to within 10 dB and 20 dB were significantly worse in the congenital group. CONCLUSION: Closure of the air-bone gap in this population differs from our results in stapedectomy done for otosclerosis. This difference likely reflects subtle anatomic variations in the congenital group that affect the effectiveness of the prosthesis. Despite the difference in results, stapedectomy for congenital fixation remains an effective method to achieve significant hearing improvement in the majority of patients. EBM RATING: B-3b.

Adolescent↗
PubMed1987

Some observations concerning 200 stapedectomies: fifteen years postoperatively.

In this study, a statistical evaluation of the hearing improvement, the incidence of postoperative tinnitus and vertigo, and the permanency of the surgically restored hearing of 120 women and 80 men operated on for otosclerosis between 1970 and 1971 was undertaken. The standardized operating procedure in all of these cases involved the use of a Gelfoam and wire prosthesis (Schuknecht 3). All patients underwent normal audiological examinations, including determination of bone and air conduction values. Pure tone thresholds were determined by averaging the values for 500, 1,000, 2,000 and 4,000 Hz. The incidence (10%) of severe sensorineural loss in regard to age, preoperative bone conduction, and oval window pathology was examined. Severe sensorineural losses had occurred immediately postoperatively in 14 of the ears. In the remaining ears, losses were gradual in the course of 15 years. Hearing thresholds in ears not subjected to operation were also determined.

Female↗
PubMedDate not supplied

Electromagnetic fields in the treatment of postmenopausal osteoporosis: an experimental study conducted by densitometric, dry ash weight and metabolic analysis of bone tissue.

The authors conducted an experimental study on 32 female rats which had been castrated at 10 months of age in order to verify the ability of pulsating electromagnetic fields to prevent osteoporosis induced by surgical menopause. Two different values of intensity of PEMFs were used: 30 G and 70 G. After 4 months of treatment the following testing was done: monophotonic bone densitometry of the lumbar spine, quantitative measurement of the dry ash weight of the femurs, and hematochemical tests to evaluate bone metabolism. The experimental study showed that the PEMFs supplied at 30 Gauss were capable of slowing down the loss of bone mass, while the PEMFs supplied at 70 Gauss obstructed bone decay, providing values for Bone Mineral Density and dry ash weight which were very similar to those observed in the non-castrated control group. Hematochemical tests did not reveal significant variations between the two groups.

Animals↗
PubMed1988

Osteoconductive composite grouts for orthopedic use.

A composite of HA particulate and calcium sulfate hemihydrate has been developed. When this dry material is mixed with either sterile saline or water, the resulting mixture begins to gel. While in the gel or dough state, the composite can be manually inserted or injected under pressure into a bone defect where it sets in situ. The calcium sulfate acts as a binder to hold the HA particles in place. The subsequent resorption of the calcium sulfate leaves controlled porosity for bone ingrowth and attachment to the nonresorbable HA particulate. The combination of calcium sulfate and HA results in a composite with handling properties superior to those of HA alone. Calcium sulfate has a long history of medical use as an implant material. The biocompatibility of the material has been clearly established. The combination of HA and calcium sulfate is likewise extremely compatible as demonstrated in the present studies. Bone ingrowth concomitant with resorption occurs rapidly with efficient conduction of bone from particle to particle. Based on the experiments presented herein, the composite of HA and calcium sulfate may be a useful alternative or adjunct to autogenous bone grafting. Many questions, however, remain regarding long-term tissue response and bone remodeling as well as the efficacy of this material relative to bone grafting.

Alveolar Process↗
PubMedDate not supplied

The bone-anchored hearing aid. Principal design and a psychoacoustical evaluation.

Hearing aids can be divided into two groups, distinguished by the principle of how sound is transmitted to the cochlea. The greatest and most important group is that consisting of air conduction (AC) hearing aids, whereas the other group consisting of bone conduction (BC) hearing aids is relatively small but nevertheless important for patients with particular types of hearing disorder. Conventional bone conduction hearing aids are not in common use, mainly because of several drawbacks. The implantation of a titanium screw into the mastoid portion of the temporal bone has made it possible to obtain a permanent and reaction-free rigid penetration of the skin. A newly developed bone conduction hearing aid was connected to such a screw. This new hearing aid is named 'the bone-anchored hearing aid' (BAHA) and it is characterized by a single housing construction. The transducer piston of the BAHA is directly connected to the titanium screw by a low-profile coupling arrangement. Ten patients were equipped with this new hearing system. In a comprehensive questionnaire, all patients reported that they preferred the BAHA to their old hearing aid. The major reasons were improvements in practical arrangements, wearing comfort, aesthetic appearance, and sound quality. Improvements in speech reception were not verified by the discrimination tests, but 6 out of 10 patients subjectively reported clearly improved sound quality. The group of patients who may benefit from the BAHA of present standard includes patients with a sensorineural hearing loss of at most 50-60 dB HL.

Adolescent↗
PubMed1994

Symbiosis of biotechnology and biomaterials: applications in tissue engineering of bone and cartilage.

The three ingredients for the successful tissue engineering of bone and cartilage are regulatory signals, cells, and extracellular matrix. Recent advances in cellular and molecular biology of the growth and differentiation factors have set the stage for a symbiosis of biotechnology and biomaterials. Recent advances permit one to enunciate the rules of architecture for tissue engineering of bone and cartilage. The purification and cloning of bone morphogenetic proteins (BMPs) and growth factors such as platelet derived growth factors (PDGF), transforming growth factor-beta (TGF-beta), and insulin-like growth factors (IGF-I) will allow the design of an optimal combination of signals to initiate and promote development of skeletal stem cells into cartilage and bone. Successful and optimal bone and cartilage formation is a synergy of inductive and conductive strategies governed by biomechanics, optimal load bearing, and motion. BMPs function as inductive signals. Biomaterials (both natural and synthetic) mimic the extracellular matrix and play a role in conduction of bone and cartilage. Examples of biomaterials include hydroxyapatite, polyanhydrides, polyphosphoesters, polylactic acid, and polyglycolic acid. The prospects for novel biomaterials are immense, and they likely will be a fertile growth industry. Cooperative ventures between academia and industry and technology transfer from the federal government augur well for an exciting future for clinical applications.

Animals↗
PubMed1998

Errors in quantitative backscattered electron analysis of bone standardized by energy-dispersive x-ray spectrometry.

Backscattered electron (BSE) imaging has proven to be a useful method for analyzing the mineral distribution in microscopic regions of bone. However, an accepted method of standardization has not been developed, limiting the utility of BSE imaging for truly quantitative analysis. Previous work has suggested that BSE images can be standardized by energy-dispersive x-ray spectrometry (EDX). Unfortunately, EDX-standardized BSE images tend to underestimate the mineral content of bone when compared with traditional ash measurements. The goal of this study is to investigate the nature of the deficit between EDX-standardized BSE images and ash measurements. A series of analytical standards, ashed bone specimens, and unembedded bone specimens were investigated to determine the source of the deficit previously reported. The primary source of error was found to be inaccurate ZAF corrections to account for the organic phase of the bone matrix. Conductive coatings, methylmethacrylate embedding media, and minor elemental constituents in bone mineral introduced negligible errors. It is suggested that the errors would remain constant and an empirical correction could be used to account for the deficit. However, extensive preliminary testing of the analysis equipment is essential.

Animals↗
PubMed2006

Effects of hearing level on habitual sniffing in patients with cholesteatoma.

CONCLUSIONS: Quality of hearing is one of the key conditions promoting habitual sniffing associated with closing failure of the Eustachian tube and sniffing may stop with deterioration of hearing due to progression of the disease. OBJECTIVE: To examine habitual sniffing associated with closing failure of the Eustachian tube and hearing level in patients with cholesteatoma. PATIENTS AND METHODS: A total of 171 patients with middle ear cholesteatoma treated in Tohoku University Hospital (106 sides in 101 patients, 63 males and 38 females, mean age 43.3 years), and Sendai Ear Surgi Center (70 sides in 70 patients, 37 males and 33 females, mean age 42.7 years) were included. The patients were divided into two groups based on the presence or absence of habitual sniffing, and pre- and postoperative hearing was compared between the two groups. RESULTS: Habitual sniffing was not found in patients with air conduction hearing level worse than 60 dB or air-bone gap larger than 40 dB. Habitual sniffing disappeared in all patients with expanded air-bone gaps in lower frequency regions after surgery.

Adult↗
PubMed1986

A speech-to-noise ratio test with the bone-anchored hearing aid: a comparative study.

Hitherto, for persons with impaired hearing who cannot use an air conduction hearing aid, the only alternative has been a conventional spring-loaded bone conduction hearing aid. Now, with minor surgery, a titanium screw can be implanted in the bone behind the ear and a coupling, which penetrates the skin, can be attached, giving a new kind of hearing aid--the "bone-anchored hearing aid." Improved quality of sound is one of the patients' subjective assessments. Improvement was not confirmed by a standard speech-discrimination test. With new speech material consisting of sentences in noise, the speech-to-noise ration (SN) has been determined for 24 patients. Patients who previously used a conventional bone conduction hearing aid improved their SN on the average by 3.3 dB. The most important difference between the two aids related to improved SN is probably the increased audibility between 600 and 6000 Hz.

Adolescent↗
PubMed2002

[Surgical treatment of inflammatory labyrinthine fistulae 23 cases].

OBJECTIVE: To report the experience of surgical treatment of inflammatory labyrinthine fistula (LF). METHOD: Twenty-three patients with cholesteatomatous otitis media complicated with LF underwent mastoidectomy, surgical repair and obliteration of LF. After removal of cholesteatoma matrix and inflammatory lesion around fistula, the fistulae were treated as following procedures: fistulae less than 2 mm in diameter were overlaid with fascia (7 cases), those 2 to 3 mm were obliterated with bone chips and fascia (13 cases), and for those more than 3 mm, the bony semicircular canal lumen were packed with fascia and bone chips, then overlaid with fascia. RESULT: In 23 patients with LF, which included 22 lateral semicircular canal fistulae (SCF) and one lateral combined with posterior SCF, two patients lost follow-up and 21 cases were observed with an average follow-up period of 2.5 years. In this series of cases, vertigo disappeared in 17 and diminished in 2. With the exception of total deafness in two cases, the average auditory thresholds in speech frequencies remained unchanged, showing that the thresholds of air conduction (AC) and bone conduction (BC) were 67.1 dB HL and 37.1 dB HL prior operation versus 69.1 dB HL and 30.6 dB HL after operation, respectively. CONCLUSION: Because of structural barrier between superior and inferior labyrinth and inflammatory adhesions, surgical treatment of inflammatory LF is feasible and effective. Successful operation depends on excellent microsurgery skill, complete removal of inflammatory lesion, precise obliteration of fistula, post-operative administration of antibiotics and steroids and close follow-up. In addition to fistula test, axial petrous bone CT scan is a good complemental method in preoperative diagnosis of LF.

Adult↗